Since this is home based studio, I would go for LEDs or Fluorescent.
Cheaper once will add extra green throw, which in this case can actually be a good thing.
Leds will not change temperature if you dim them, and will not flick; you can also have a small mixer console for fine tuning.
They will also save space, can be soft , directional, thus will not create much spill.
15 feet hight is also consideration, where led or kino setup would be better.
I would not go with tungsten as it'll generate heat , eats electricity and takes more space.
Where exactly do you live, I could swing by next week with my lights and give you a hand.
I am in Missisauga and often need small studio:)
My fav. setup is space light as it gives me nice and even f-stop across the stage.
This studio was about the same size (20 feet high) and we used space lights. In spite of good ventilation it was hot.